# import matplotlib.pyplot as plt
# #
# # # 数据
# # x = [1, 2, 3, 4, 5]
# # y = [10, 20, 25, 30, 22]
# #
# # # 绘制线图
# # plt.plot(x, y)
# #
# # # 保存图片  //  必须在  show() 之前调用 ， 否则会出现空白
# # plt.savefig('./plt_imgs/subplots_example.png')
# #
# # # 显示图形
# # plt.show()


import numpy as np

#　<class 'numpy.ndarray'>
# print(type(np.array([1, 2, 3])))

#　<class 'numpy.ndarray'>
# print(type(np.array([[1, 2, 3], [4, 5, 6]])))

#  [0, 1) ， 步长为 0.1
#　[0.  0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9]
#　print(np.arange(0, 1, 0.1))

# a = [ 1 11 21 31 41 51]
# 一阶
# a = np.arange(1, 60, 10)
'''
# 二阶
b=
[[ 1]
 [11]
 [21]
 [31]
 [41]
 [51]]
'''
# 转成1列
# b = a.reshape(-1, 1)
# c = [0 1 2 3 4 5]
# c = np.arange(0, 6)
'''
[[ 1  2  3  4  5  6]
 [11 12 13 14 15 16]
 [21 22 23 24 25 26]
 [31 32 33 34 35 36]
 [41 42 43 44 45 46]
 [51 52 53 54 55 56]]
'''
# d = b + c
# print(d)

'''
 [0.   0.11111111 0.22222222 0.33333333 0.44444444 0.55555556
       0.66666667 0.77777778 0.88888889 1.        ]
'''
# [0, 1], 等差数列：  1 / (10 - 1)
# print(np.linspace(0, 1, 10))

'''
[  1.           1.27427499   1.62377674   2.06913808   2.6366509
   3.35981829   4.2813324    5.45559478   6.95192796   8.8586679
  11.28837892  14.38449888  18.32980711  23.35721469  29.76351442
  37.92690191  48.32930239  61.58482111  78.47599704 100.        ]
'''
# x=np.logspace(0, 2, 20)
# # (20,)
# print(x.shape)



